NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
1) Introduction
a) In recent years, a greater emphasis has been placed on the study of the organic basis for psychiatric illness.
b) Several mental illnesses are now being considered as physical disorders that are the result of malfunctions and/or
malformation in the brain
2) The Nervous System: Review
a) The Brain
i) Forebrain
(1) Cerebrum
(a) Composed of two hemispheres separated by grooves that house a band of neurons called the corpus callosum
(b) Largest part of the brain
(c) Outer shell is called the cerebral cortex
(i) Folds are called gyri; and grooves are called sulci
(ii) Gray matter (no myelin) – neuron cell bodies composes the cortex
1. Thought to be thinking structure of the brain
(d) Basal ganglia is also gray matter found deep in cerebral hemispheres
(i) Responsible for certain subconscious aspects of voluntary movement – such as: swinging of arms
when walking, gesturing while speaking, and regulating muscle tone
(e) Left hemisphere deals with logic and problem solving
(f) Right hemisphere is the creative brain and is associated with affect, behavior, and spatial-perceptual functions
(g) Hemispheres are divided into 4 lobes
(i) The frontal lobe
1. Voluntary body movement
a. Movements that permit speaking, thinking and judgment formation, and expression of feelings
i. Movements that permit speaking are usually controlled by the left side
2. May also play a role in emotional experience – evident by changes in mood and character after
damage to this area
a. Alterations include fear, aggressiveness, depression, rage, euphoria, irritability, and apathy
b. Likely related to frontal lobe connection to the limbic system
3. May also be involved indirectly through association fibers linked to primary sensory areas in thinking
and perceptual interpretation of information
4. Right frontal lobe control motor activity on the left side
5. Left frontal lobe control motor activity on the right side
(ii) The parietal lobe
1. Perception and interpretation of most sensory information
a. Touch, pain, pressure, taste, temperature, perception of joint and body position, and
visceral sensations
2. Interpretation of sensory-perceptual information is made
3. Language interpretation is associated with the left hemisphere of the partial lobe
(iii) The temporal lobe
1. Hearing, short term memory, and sense of smell
a. The upper anterior lobe is concerned with auditory functions
b. The lower part is dedicated to short term memory
c. Sense of smell has connection as the impulses carried by the olfactory nerves end in this area of
the brain
2. Expression of emotions through connection with the limbic system
3. The left temporal lobe, along with the left parietal lobe, is involved in language interpretation
(iv) The occipital lobe
1. Visual reception and interpretation
2. Visual perception (ability to judge spatial relationships such as distance and to see in 3 dimensions)
is processed in this area
3. Language interpretation is influenced by the occipital lobes through association with the
NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
, NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
visual experience
(2) Diencephalon
(a) Connects the cerebrum with lower structures of the brain
(b) 3 components
(i) Thalamus
1. Integrates all sensory input (except smell) on its way to cortex; some involvement with emotions
and mood
a. Helps cerebral cortex interpret the whole picture rapidly, rather than experiencing each
sensation individually
2. Involved in temporarily blocking minor sensations, so person can concentrate on one important
event when necessary
a. Example: person studying for exam may be unaware of ticking clock
(ii) Hypothalamus
1. Regulates anterior and posterior lobes of pituitary gland; exerts control over actions of the
autonomic nervous system; regulates appetite and temperature
2. Regulation of pituitary gland
a. Posterior lobe of pituitary gland is extended tissue from the hypothalamus
b. Stores antidiuretic hormone helps to maintain BP through water retention
c. Stores oxytocin – responsible for uterine stimulation during labor, and release of milk in
mammary glands
d. Antidiuretic hormone and oxytocin are produced by the hypothalamus
i. Pituitary gland stores these hormones and then releases them
3. Direct neural control over the actions of the autonomic nervous system
a. Regulates visceral responses during various emotional states
4. Regulation of appetite
a. Regulated through response to blood nutrient levels
5. Regulation of temperature
a. Hypothalamus senses internal temperature changes in the blood that flows through the brain
b. Receives information through sensory input from the skin about external temperature changes
c. Promotes certain responses such as shivering or sweating – helps maintain body temp in
normal ranges
(iii) Limbic system
1. Consist of medially placed cortical and subcortical structures and the fiber tracts connecting them
with one another and the hypothalamus
2. The system is composed of amygdala, mammillary body, olfactory tract, hypothalamus, cingulate
gyrus, septum pellucidum, thalamus, hippocampus, and neuronal connecting pathways
a. Sometimes called emotional brain – associated with feelings or fear and anxiety; anger
and aggression; love and joy, and hope; and with sexuality and social behavior
ii) Midbrain
(1) Mesencephalon
(a) Responsible for visual, auditory, and balance (righting) reflexes
(b) Nuclei and fiber tracts
(c) Extends from the pons to the hypothalamus
(d) Responsible for visual reflexes (automatically turning around from dangerous object when it comes into view),
auditory reflexes (automatically turning toward a sound that is heard), and righting reflexes (automatically
keeping the head upright and maintaining balance)
iii) Hindbrain
(1) Pons
(a) Regulation of respiration and skeletal muscle tone; ascending and descending tracts connect brainstem
with cerebellum and cortex
(b) Lies between midbrain and medulla
(c) Contains the central connections of cranial nerves V through VIII and centers for respirations and skeletal
muscle tone
NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
, NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
(2) Medulla
(a) Pathway for all ascending and descending fiber tracts; contains vital centers that regulate HR, BP, and
respiration; reflex centers for swallowing, sneezing, coughing, and vomiting
(b) Connecting structure between spinal cord and the pons
(c) Contains nuclei for cranial nerves IX through XII
(3) Cerebellum
(a) Regulates muscle tone and coordination and maintains posture and equilibrium
(i) Involuntary movement
(b) Separated from the brainstem by the 4th ventricle but has connections to the brainstem through bundles of
fiber tracts
(c) Situated just below occipital lobes
3) The Nervous System: Review
a) Nerve Tissue
i) Neurons (generate and transmit electrochemical impulses) - composed of
(1) Cell body
(a) Contains the nucleus and is essential for the continued life of the neuron
(2) Axons
(a) Transmits impulses away from cell body
(b) Myelin sheath (white matter)
(3) Dendrites
(a) Processes that transmit impulses toward the cell body
(b) Myelin sheath (white matter)
ii) Classes of neurons
(1) Afferent (sensory)
(a) Carry impulses from the receptors in the internal and external periphery to the CNS, where they are
then interpreted into various sensations
(2) Efferent (motor)
(a) Carry impulses from the CNS to effectors in the periphery, such as muscles that respond by contracting, and
glands that respond by secreting
(3) Interneurons
(a) Exist entirely in the CNS, and 99% of all nerve cells belong in this group
(b) Account in large part for thinking, feeling, learning, language, and memory
iii) Synapses
(1) Junction between two neurons
(2) The small space between the axon terminals of one neuron and he cell body or dendrites of another is called
the synaptic cleft
(3) Neurons conducting impulses toward the synapse are called presynaptic neurons and those conducting impulses
away are called postsynaptic neurons
iv) Neurotransmitters
(1) Stored in the axon terminals of the presynaptic neuron
(2) An electrical impulse through the neuron causes the release of the neurotransmitter into the synaptic cleft
(3) Neurotransmitter then diffuses across the cleft and combines with receptor sites that are situated on the
cell membrane of the postsynaptic cleft
(a) Result of combination of neurotransmitter-receptor site is the determination of whether or not another
electrical impulse is generated
(b) If one is generated the result is called an excitatory response and the electrical impulse moves onto the
next synapse
(c) If another electrical impulse is not generated by the neurotransmitter-receptor site combination, the result
is called an inhibitory response, and synaptic transmission is terminated
(4) The cell body or dendrite of the postsynaptic neuron also contains a chemical inactivator that is specific to
the neurotransmitter that has been released by the presynaptic neuron
(a) When the synaptic transmission has been completed, the chemical inactivator quickly inactivates the
NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
, NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
neurotransmitter to prevent unwanted, continuous impulses, until a new impulse from the presynaptic
neuron releases more neurotransmitter
4) The Nervous System: Review
a) Neurotransmitters play an important role in human emotions and behavior, and are the target for the mechanism of action
in many psychotropic medications
b) Chemicals that convey information across synaptic cleft to neighboring target cells
c) When the action potential reaches the axons terminals, the neurotransmitters are released from the vesicles
d) They cross the synaptic cleft and bind with receptor sites on the cell body or dendrites of the adjacent neuron to allow
the impulse to continue its course or to prevent the impulse from continuing
e) Process of being stored for reuse is called reuptake
f) Major categories of neurotransmitters
i) Cholinergics
(1) Acetylcholine
(a) Location
(i) Autonomic nervous system: sympathetic and parasympathetic presynaptic never terminals;
parasympathetic postsynaptic nerve terminals
(ii) Central nervous system: cerebral cortex, hippocampus, limbic structures, and basal ganglia
(b) Functions
(i) Sleep, arousal, pain perception, modulation and coordination of movement, and memory acquisition
and retention
(c) Possible implications for mental illness
(i) Increased levels: depression
(ii) Decreased levels: Alzheimer’s disease, Huntington’s disease, and Parkinson’s disease
(d) Notes
(i) Acetylcholinesterase is the enzyme that breaks down/destroys acetylcholine activity
ii) Monoamines
(1) Norepinephrine
(a) Location
(i) Autonomic nervous system: sympathetic postsynaptic nerve terminals
1. Resulting in the fight or flight response
(ii) Central nervous system: thalamus, hypothalamus, limbic system, hippocampus, cerebellum, cerebral cortex
(b) Function
(i) Mood, cognition, perception, locomotion, cardiovascular functioning, sleep, and arousal
(c) Possible implications for mental illness
(i) Decreased level: depression
(ii) Increased level: mania, anxiety states, and schizophrenia
(d) Notes
(i) When norepinephrine is not returned for storage in the vesicles of the axon terminals, it is metabolized
and inactivated by the enzyme monoamine oxidase (MAO) and catechol-O-methyltransferase (COMT)
(2) Dopamine
(a) Location
(i) Frontal cortex, limbic system, basal ganglia, thalamus, posterior pituitary, and spinal cord
(b) Function
(i) Movement and coordination, emotions, voluntary judgment, inhibits release of prolactin
(c) Possible implications for mental illness
(i) Decreased levels: Parkinson’s disease and depression
(ii) Increased levels: mania and schizophrenia!
(d) Notes
(i) Inactivating enzymes are MAO and COMT
1. Monoamine oxidase (MAO) and catechol-O-methyltransferase (COMT)
(3) Serotonin
NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
review 2022 update graded A+
1) Introduction
a) In recent years, a greater emphasis has been placed on the study of the organic basis for psychiatric illness.
b) Several mental illnesses are now being considered as physical disorders that are the result of malfunctions and/or
malformation in the brain
2) The Nervous System: Review
a) The Brain
i) Forebrain
(1) Cerebrum
(a) Composed of two hemispheres separated by grooves that house a band of neurons called the corpus callosum
(b) Largest part of the brain
(c) Outer shell is called the cerebral cortex
(i) Folds are called gyri; and grooves are called sulci
(ii) Gray matter (no myelin) – neuron cell bodies composes the cortex
1. Thought to be thinking structure of the brain
(d) Basal ganglia is also gray matter found deep in cerebral hemispheres
(i) Responsible for certain subconscious aspects of voluntary movement – such as: swinging of arms
when walking, gesturing while speaking, and regulating muscle tone
(e) Left hemisphere deals with logic and problem solving
(f) Right hemisphere is the creative brain and is associated with affect, behavior, and spatial-perceptual functions
(g) Hemispheres are divided into 4 lobes
(i) The frontal lobe
1. Voluntary body movement
a. Movements that permit speaking, thinking and judgment formation, and expression of feelings
i. Movements that permit speaking are usually controlled by the left side
2. May also play a role in emotional experience – evident by changes in mood and character after
damage to this area
a. Alterations include fear, aggressiveness, depression, rage, euphoria, irritability, and apathy
b. Likely related to frontal lobe connection to the limbic system
3. May also be involved indirectly through association fibers linked to primary sensory areas in thinking
and perceptual interpretation of information
4. Right frontal lobe control motor activity on the left side
5. Left frontal lobe control motor activity on the right side
(ii) The parietal lobe
1. Perception and interpretation of most sensory information
a. Touch, pain, pressure, taste, temperature, perception of joint and body position, and
visceral sensations
2. Interpretation of sensory-perceptual information is made
3. Language interpretation is associated with the left hemisphere of the partial lobe
(iii) The temporal lobe
1. Hearing, short term memory, and sense of smell
a. The upper anterior lobe is concerned with auditory functions
b. The lower part is dedicated to short term memory
c. Sense of smell has connection as the impulses carried by the olfactory nerves end in this area of
the brain
2. Expression of emotions through connection with the limbic system
3. The left temporal lobe, along with the left parietal lobe, is involved in language interpretation
(iv) The occipital lobe
1. Visual reception and interpretation
2. Visual perception (ability to judge spatial relationships such as distance and to see in 3 dimensions)
is processed in this area
3. Language interpretation is influenced by the occipital lobes through association with the
NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
, NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
visual experience
(2) Diencephalon
(a) Connects the cerebrum with lower structures of the brain
(b) 3 components
(i) Thalamus
1. Integrates all sensory input (except smell) on its way to cortex; some involvement with emotions
and mood
a. Helps cerebral cortex interpret the whole picture rapidly, rather than experiencing each
sensation individually
2. Involved in temporarily blocking minor sensations, so person can concentrate on one important
event when necessary
a. Example: person studying for exam may be unaware of ticking clock
(ii) Hypothalamus
1. Regulates anterior and posterior lobes of pituitary gland; exerts control over actions of the
autonomic nervous system; regulates appetite and temperature
2. Regulation of pituitary gland
a. Posterior lobe of pituitary gland is extended tissue from the hypothalamus
b. Stores antidiuretic hormone helps to maintain BP through water retention
c. Stores oxytocin – responsible for uterine stimulation during labor, and release of milk in
mammary glands
d. Antidiuretic hormone and oxytocin are produced by the hypothalamus
i. Pituitary gland stores these hormones and then releases them
3. Direct neural control over the actions of the autonomic nervous system
a. Regulates visceral responses during various emotional states
4. Regulation of appetite
a. Regulated through response to blood nutrient levels
5. Regulation of temperature
a. Hypothalamus senses internal temperature changes in the blood that flows through the brain
b. Receives information through sensory input from the skin about external temperature changes
c. Promotes certain responses such as shivering or sweating – helps maintain body temp in
normal ranges
(iii) Limbic system
1. Consist of medially placed cortical and subcortical structures and the fiber tracts connecting them
with one another and the hypothalamus
2. The system is composed of amygdala, mammillary body, olfactory tract, hypothalamus, cingulate
gyrus, septum pellucidum, thalamus, hippocampus, and neuronal connecting pathways
a. Sometimes called emotional brain – associated with feelings or fear and anxiety; anger
and aggression; love and joy, and hope; and with sexuality and social behavior
ii) Midbrain
(1) Mesencephalon
(a) Responsible for visual, auditory, and balance (righting) reflexes
(b) Nuclei and fiber tracts
(c) Extends from the pons to the hypothalamus
(d) Responsible for visual reflexes (automatically turning around from dangerous object when it comes into view),
auditory reflexes (automatically turning toward a sound that is heard), and righting reflexes (automatically
keeping the head upright and maintaining balance)
iii) Hindbrain
(1) Pons
(a) Regulation of respiration and skeletal muscle tone; ascending and descending tracts connect brainstem
with cerebellum and cortex
(b) Lies between midbrain and medulla
(c) Contains the central connections of cranial nerves V through VIII and centers for respirations and skeletal
muscle tone
NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
, NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
(2) Medulla
(a) Pathway for all ascending and descending fiber tracts; contains vital centers that regulate HR, BP, and
respiration; reflex centers for swallowing, sneezing, coughing, and vomiting
(b) Connecting structure between spinal cord and the pons
(c) Contains nuclei for cranial nerves IX through XII
(3) Cerebellum
(a) Regulates muscle tone and coordination and maintains posture and equilibrium
(i) Involuntary movement
(b) Separated from the brainstem by the 4th ventricle but has connections to the brainstem through bundles of
fiber tracts
(c) Situated just below occipital lobes
3) The Nervous System: Review
a) Nerve Tissue
i) Neurons (generate and transmit electrochemical impulses) - composed of
(1) Cell body
(a) Contains the nucleus and is essential for the continued life of the neuron
(2) Axons
(a) Transmits impulses away from cell body
(b) Myelin sheath (white matter)
(3) Dendrites
(a) Processes that transmit impulses toward the cell body
(b) Myelin sheath (white matter)
ii) Classes of neurons
(1) Afferent (sensory)
(a) Carry impulses from the receptors in the internal and external periphery to the CNS, where they are
then interpreted into various sensations
(2) Efferent (motor)
(a) Carry impulses from the CNS to effectors in the periphery, such as muscles that respond by contracting, and
glands that respond by secreting
(3) Interneurons
(a) Exist entirely in the CNS, and 99% of all nerve cells belong in this group
(b) Account in large part for thinking, feeling, learning, language, and memory
iii) Synapses
(1) Junction between two neurons
(2) The small space between the axon terminals of one neuron and he cell body or dendrites of another is called
the synaptic cleft
(3) Neurons conducting impulses toward the synapse are called presynaptic neurons and those conducting impulses
away are called postsynaptic neurons
iv) Neurotransmitters
(1) Stored in the axon terminals of the presynaptic neuron
(2) An electrical impulse through the neuron causes the release of the neurotransmitter into the synaptic cleft
(3) Neurotransmitter then diffuses across the cleft and combines with receptor sites that are situated on the
cell membrane of the postsynaptic cleft
(a) Result of combination of neurotransmitter-receptor site is the determination of whether or not another
electrical impulse is generated
(b) If one is generated the result is called an excitatory response and the electrical impulse moves onto the
next synapse
(c) If another electrical impulse is not generated by the neurotransmitter-receptor site combination, the result
is called an inhibitory response, and synaptic transmission is terminated
(4) The cell body or dendrite of the postsynaptic neuron also contains a chemical inactivator that is specific to
the neurotransmitter that has been released by the presynaptic neuron
(a) When the synaptic transmission has been completed, the chemical inactivator quickly inactivates the
NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
, NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
neurotransmitter to prevent unwanted, continuous impulses, until a new impulse from the presynaptic
neuron releases more neurotransmitter
4) The Nervous System: Review
a) Neurotransmitters play an important role in human emotions and behavior, and are the target for the mechanism of action
in many psychotropic medications
b) Chemicals that convey information across synaptic cleft to neighboring target cells
c) When the action potential reaches the axons terminals, the neurotransmitters are released from the vesicles
d) They cross the synaptic cleft and bind with receptor sites on the cell body or dendrites of the adjacent neuron to allow
the impulse to continue its course or to prevent the impulse from continuing
e) Process of being stored for reuse is called reuptake
f) Major categories of neurotransmitters
i) Cholinergics
(1) Acetylcholine
(a) Location
(i) Autonomic nervous system: sympathetic and parasympathetic presynaptic never terminals;
parasympathetic postsynaptic nerve terminals
(ii) Central nervous system: cerebral cortex, hippocampus, limbic structures, and basal ganglia
(b) Functions
(i) Sleep, arousal, pain perception, modulation and coordination of movement, and memory acquisition
and retention
(c) Possible implications for mental illness
(i) Increased levels: depression
(ii) Decreased levels: Alzheimer’s disease, Huntington’s disease, and Parkinson’s disease
(d) Notes
(i) Acetylcholinesterase is the enzyme that breaks down/destroys acetylcholine activity
ii) Monoamines
(1) Norepinephrine
(a) Location
(i) Autonomic nervous system: sympathetic postsynaptic nerve terminals
1. Resulting in the fight or flight response
(ii) Central nervous system: thalamus, hypothalamus, limbic system, hippocampus, cerebellum, cerebral cortex
(b) Function
(i) Mood, cognition, perception, locomotion, cardiovascular functioning, sleep, and arousal
(c) Possible implications for mental illness
(i) Decreased level: depression
(ii) Increased level: mania, anxiety states, and schizophrenia
(d) Notes
(i) When norepinephrine is not returned for storage in the vesicles of the axon terminals, it is metabolized
and inactivated by the enzyme monoamine oxidase (MAO) and catechol-O-methyltransferase (COMT)
(2) Dopamine
(a) Location
(i) Frontal cortex, limbic system, basal ganglia, thalamus, posterior pituitary, and spinal cord
(b) Function
(i) Movement and coordination, emotions, voluntary judgment, inhibits release of prolactin
(c) Possible implications for mental illness
(i) Decreased levels: Parkinson’s disease and depression
(ii) Increased levels: mania and schizophrenia!
(d) Notes
(i) Inactivating enzymes are MAO and COMT
1. Monoamine oxidase (MAO) and catechol-O-methyltransferase (COMT)
(3) Serotonin
NUR 4120 ch 4:concepts of psychobiology exam practice
review 2022 update graded A+
